Bronchiolitis: Analysis of 10 consecutive epidemic seasons.

Bronchiolitis is the leading cause of hospitalization in infants under 12 months. Our aims were to analyze epidemiological characteristics of infants with bronchiolitis over 10 consecutive seasons and to evaluate whether there are any clinical differences between infants hospitalized for bronchiolitis during epidemic peak months and infants in non-peak months. We enrolled consecutive enrolled 723 previously healthy term infants hospitalized at the Paediatric Emergency Department, "Sapienza" University of Rome over the period 2004-2014. Fourteen respiratory viruses were detected from nasopharyngeal aspirates by molecular methods. Clinical and demographic data were extracted from clinical charts. Viruses were detected in 351 infants (48.5%): RSV in 234 (32.4%), RV in 44 (6.1%), hBoV in 11 (1.5%), hMPV in 12 (1.6%), co-infections in 39 (5.4%), and other viruses in 11 (1.5%). Analyzing the 10 epidemic seasons, we found higher incidence for bronchiolitis every 4 years with a peak during the months December-January. Infants hospitalized during peak months had lower family history for asthma (P = 0.003), more smoking mothers during pregnancy (P = 0.036), were slightly higher breastfed (0.056), had lower number of blood eosinophils (P = 0.015) and had a higher clinical severity score (P = 0.017). RSV was detected mostly during peak months, while RV was equally distributed during the seasons. We found some variations in bronchiolitis incidence during epidemics, and discriminative characteristics in infants hospitalized for bronchiolitis during peak months and in non-peak months, that might reflect two different populations of children. Pediatr Pulmonol. 2016;51:1330-1335. © 2016 Wiley Periodicals, Inc.

Cangiano G ，Nenna R ，Frassanito A ，Evangelisti M ，Nicolai A ，Scagnolari C ，Pierangeli A ，Antonelli G ，Papoff P ，Petrarca L ，Capocaccia P ，Moretti C ，Midulla F ... -  《-》

Respiratory syncytial virus, human bocavirus and rhinovirus bronchiolitis in infants.

To investigate the prevalence of 14 viruses in infants with bronchiolitis and to study demographic and clinical differences in those with respiratory syncytial virus (RSV), human bocavirus (hBoV) and rhinovirus (RV) infection. 182 infants aged <12 months hospitalised for bronchiolitis were enrolled. Infants underwent nasal washing for the detection of RSV, influenza virus A and B, human coronavirus OC43, 229E, NL-63, HUK1, adenovirus, RV, parainfluenza 1-3, human metapneumovirus and hBoV. Demographic, clinical and laboratory data were obtained from parents and from patient medical files. Main outcome measurements were age, breastfeeding history, family smoking habits, family history for asthma and atopy, blood eosinophil count, chest radiological findings, clinical severity score and number of days of hospitalisation. A virus was detected in 57.2% of the 182 infants. The most frequently detected viruses were RSV (41.2%), hBoV (12.2%) and RV (8.8%). Infants with dual infections (RSV and hBoV) had a higher clinical severity score and more days of hospitalisation than infants with RSV, RV and hBoV bronchiolitis (mean+/-SD: 4.7+2.4 vs 4.3+/-2.4 vs 3.0+/-2.0 vs 2.9+/-1.7, p<0.05; and 6.0+/-3.2 vs 5.3+/-2.4 vs 4.0+/-1.6 vs 3.9+/-1.1 days; p<0.05). Infants with RV infection had higher blood eosinophil counts than infants with bronchiolitis from RSV and hBoV (307+/-436 vs 138+/-168 vs 89+/-19 n/mm(3); p<0.05). Although the major pathogen responsible for bronchiolitis remains RSV, the infection can also be caused by RV and hBoV. Demographic characteristics and clinical severity of the disease may depend on the number of viruses or on the specific virus detected.

Midulla F ，Scagnolari C ，Bonci E ，Pierangeli A ，Antonelli G ，De Angelis D ，Berardi R ，Moretti C ... -  《-》

[Determination of the frequency of human bocavirus and other respiratory viruses among 0-2 years age group children diagnosed as acute bronchiolitis].

Uyar M ，Kuyucu N ，Tezcan S ，Aslan G ，Tasdelen B ... -  《MIKROBIYOLOJI BULTENI》

Infections and coinfections by respiratory human bocavirus during eight seasons in hospitalized children.

The human bocavirus (hBoV) has been identified in respiratory infections in children in a large number of studies. Despite this, the pathogenic role of the HBoV is under discussion. The main objectives of the study were: to determine the incidence of HBoV in hospitalized children; to describe the main clinical features of the positive children; and to compare the data with those from other viral infections in the same population. A prospective study was performed between 2005 and 2013 including children up to 14-year old with respiratory infection admitted to the Severo Ochoa Hospital (Spain). Nasopharyngeal aspirates were taken from 3,275 patients and were tested for HBoV and other 15 respiratory viruses by RT-nested PCR. HBoV was detected in 319 patients (9.9%); 80 cases as a single pathogen, and 239 cases (75%) as coinfections with other viruses. The HBoV was the fourth most common virus detected, behind respiratory syncytial virus (39.8%), rhinovirus (30.6%), and adenovirus (15%). The most common clinical diagnosis, in cases that HBoV was detected as a single pathogen was asthma exacerbation followed by pneumonia. A seasonal distribution was shown, with higher positivity rates in December and January. Children affected by HBoV were older than children infected by other viruses. Differences in terms of clinical diagnosis were found, bronchiolitis diagnosis was lower compared with the other viruses, and HBoV was associated with diagnosis of pneumonia, with increased use of antibiotics (41.8%), and radiographic infiltrates (47%). These findings could suggest a pathogenic role of HBoV in respiratory infections in children under 14 years of age. J. Med. Virol. 88:2052-2058, 2016. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Calvo C ，García-García ML ，Pozo F ，Carballo D ，Martínez-Monteserín E ，Casas I ... -  《-》

Neutrophil infiltration and activation in bronchiolitic airways are independent of viral etiology.

Hospitalization with bronchiolitis is linked to the development of early childhood chronic wheeze and asthma. Viral etiology and severity of inflammation are potential contributing factors. Previously we observed reduced airway neutrophil infiltration in breastfed bronchiolitic infants, with a corresponding reduction in disease severity. This study aimed to examine whether respiratory viral etiology and co-infection alters the pattern of neutrophil influx, and the inflammatory mediator profile, resulting in epithelial damage in bronchiolitis. Nasopharyngeal aspirates (NPAs) collected from hospitalized infants were assessed for viruses, soluble protein, cellular infiltrate, interleukin (IL)-6, -8, and myeloperoxidase (MPO). NPAs were collected from 228 bronchiolitic and 14 non-bronchiolitic infants. In the bronchiolitic cohort, human rhinovirus was most prevalent (38%), followed by respiratory syncytial virus (36%), adenovirus (10%), and human metapneumovirus (6%), with 25% positive for viral co-infections and 25% negative for all screened viruses. Viral-induced bronchiolitis was associated with increased cellular infiltrate and protein, above control, and virus-negative infants (P < 0.05). Cellular infiltrate correlated to IL-6, -8, and MPO (r = 0.331, 0.669, and 0.661; P < 0.01). Protein, IL-6, -8, and MPO differed significantly between viral groups; however, the majority of marker values for all groups fall within an overlapping, indistinguishable range, precluding their use as biomarkers of viral etiology. No significant difference was found between single and viral co-infections for any parameter. Bronchiolitic infants presenting with a detectable respiratory virus during hospitalization demonstrated elevated markers of airway tissue inflammation and injury. In this cohort, viral etiology did not discernibly modulate chemokine-mediated neutrophil infiltration and activation. Pediatr Pulmonol. 2017;52:238-246. © 2016 Wiley Periodicals, Inc.

Cavallaro EC ，Liang KK ，Lawrence MD ，Forsyth KD ，Dixon DL ... -  《-》